Protocol for Partner2Lose: A randomized controlled trial to evaluate partner involvement on long-term weight loss

Primary outcomes from Partner2Lose: A randomized controlled trial to evaluate partner involvement on long-term weight loss

Background

Partner support is associated with better weight loss outcomes in observational studies, but randomized trials show mixed results for including partners. Unclear is whether teaching communication skills to couples will improve weight loss in index participants.

Purpose

To compare the efficacy of a partner-assisted intervention versus participant-only weight management program on long-term weight loss.

Methods

This community-based study took place in Madison, WI. Index participants were eligible if they met obesity guideline criteria to receive weight loss counseling, were aged 74 years or younger, lived with a partner, and had no medical contraindications to weight loss; partners were aged 74 years or younger and not underweight. Couples were randomized 1:1 to a partner-assisted or participant-only intervention. Index participants in both arms received an evidence-based weight management program. In the partner-assisted arm, partners attended half of the intervention sessions, and couples were trained in communication skills. The primary outcome was index participant weight at 24 months, assessed by masked personnel; secondary outcomes were 24-month self-reported caloric intake and average daily steps assessed by an activity tracker. General linear mixed models were used to compare group differences in these outcomes following intent-to-treat principles.

Results

Among couples assigned to partner-assisted (n=115) or participant-only intervention (n=116), most index participants identified as female (67%) and non-Hispanic White (87%). Average baseline age was 47.27 years (SD 11.51 years) and weight was 106.55 kg (SD 19.41 kg). The estimated mean 24-month weight loss was similar in the partner-assisted (2.66 kg) and participant-only arms (2.89 kg) (estimated mean difference, 0.23 kg [95% CI, -1.58, 2.04 kg]). There were no differences in 24-month average daily caloric intake (50 cal [95% CI: -233, 132 cal]) or steps (806 steps [95% CI: -1675, 64 steps]). The percentage of participants reporting an adverse event with at least possible attribution to the intervention did not differ by arm (partner-assisted: 9%, participant-only, 3%, p=0.11).

Conclusions

Partner-assisted and individual weight management interventions led to similar outcomes in index participants.

Trial registration

Clinicaltrials.gov NCT03801174.

Compendium of dyadic intervention techniques (DITs) to change health behaviours: a systematic review

BACKGROUND

Dyadic interventions for health behaviour change involving the romantic partner are promising. However, it often remains unclear how exactly the partner is involved in dyadic interventions. We propose a novel compendium of dyadic intervention techniques (DITs) that facilitates systematic description of dyadic interventions in terms of who performs what for whom during intervention delivery and subsequent implementation.

OBJECTIVE

We aimed to systematically characterise dyadic interventions along their degree of partner involvement and to provide a comprehensive list of DITs used in dyadic interventions with romantic partners.

METHODS

We systematically reviewed dyadic health behaviour change interventions with controlled designs. We included 165 studies describing 122 distinct dyadic interventions with romantic partners. Interventions were classified along their degree of partner involvement, 160 DITs were extracted, and their frequencies of use counted.

RESULTS

The majority of interventions (n = 90, 74%) explicitly instructed partners to interact. Half of the DITs were performed jointly by the couple and also targeted the couple. Mostly, couples were instructed to jointly practice communication skills and to jointly perform problem solving for the couple.

DISCUSSION

The present review contributes to the development of a shared and systematic way of describing dyadic interventions to facilitate cumulation of evidence.

A Method to Deliver Automated and Tailored Intervention Content: 24-month Clinical Trial

Background

The use of digital technologies and software allows for new opportunities to communicate and engage with research participants over time. When software is coupled with automation, we can engage with research participants in a reliable and affordable manner. Research Electronic Data Capture (REDCap), a browser-based software, has the capability to send automated text messages. This feature can be used to automate delivery of tailored intervention content to research participants in interventions, offering the potential to reduce costs and improve accessibility and scalability.

Objective

This study aimed to describe the development and use of 2 REDCap databases to deliver automated intervention content and communication to index participants and their partners (dyads) in a 2-arm, 24-month weight management trial, Partner2Lose.

Methods

Partner2Lose randomized individuals with overweight or obesity and cohabitating with a partner to a weight management intervention alone or with their partner. Two databases were developed to correspond to 2 study phases: one for weight loss initiation and one for weight loss maintenance and reminders. The weight loss initiation database was programmed to send participants (in both arms) and their partners (partner-assisted arm) tailored text messages during months 1-6 of the intervention to reinforce class content and support goal achievement. The weight maintenance and reminder database was programmed to send maintenance-related text messages to each participant (both arms) and their partners (partner-assisted arm) during months 7-18. It was also programmed to send text messages to all participants and partners over the course of the 24-month trial to remind them of group classes, dietary recall and physical activity tracking for assessments, and measurement visits. All text messages were delivered via Twilio and were unidirectional.

Results

Five cohorts, comprising 231 couples, were consented and randomized in the Partner2Lose trial. The databases will send 53,518 automated, tailored text messages during the trial, significantly reducing the need for staff to send and manage intervention content over 24 months. The cost of text messaging will be approximately US $450. Thus far, there is a 0.004% known error rate in text message delivery.

Conclusions

Our trial automated the delivery of tailored intervention content and communication using REDCap. The approach described provides a framework that can be used in future behavioral health interventions to create an accessible, reliable, and affordable method for intervention delivery and engagement that requires minimal trial-specific resources and personnel time.

Trial Registration

ClinicalTrials.gov NCT03801174; https://clinicaltrials.gov/ct2/show/NCT03801174?term=NCT03801174